Montipora losing color

[gdtpgh]

I have several SPS corals I purchased about 6 weeks ago. One of them doesn't seem to be doing well. It's in the center of the tank directly under one of the 10k halides approx 8 inches under the surface of the water. The halide is approx 7 inches above the surface. It's a red Montipora Capricornis and it's losing color and the polyps aren't coming out as far. I think it has grown slightly since putting it in. I think I need to move it lower but I'm not certain. The other corals are all doing fine but they're a little lower in the tank. Is a 10k halide on for 8hrs the issue for this coral? I thought mid tank was fine give what I've read. The coral came from LiveAquaria and looked very colorful when I rec'd it.

pH, alk calcium and temp all are within acceptable limits. Since it's only this coral I am assuming it's lighting. Any thoughts?

It's a 126gal tank with three 10k halides and two actinics.

 

[Anonymous]

What wattage are your halides?
Also, what specifically are your Alk and Ca readings? They could both be "within acceptable limits" yet still be out of whack with each other.

 

[gdtpgh]

The halides are 250W HQI bulbs. Calcium was tested a week ago at 400 and the alk is 130ppm. Temp is around 80 and pH is 8.2 at night and 7.9 in the morning. I have a 20 gal refugium as part of the system and drip Kalkwasser into the sump at night making up all evaporated water. As needed I add some buffer in the morning. I do weekly 5 gal water changes. No other supplements are added.

The tank is also relatively new...less than 6 months old.

 

[Anonymous]

Do you have test kits or are you taking your water somewhere to be tested?

alk is not measured in ppm. You should get a reading of dkh (probably somewhere between 7 and 13) or meg/l (somewhere around 2.5 to 4.5).

Alk swings or simply low alk can cause SPS to lose color.

This is a great article about Ca and Alk in a reef tank


http://www.reefkeeping.com/issues/2002- ... /index.php

I don't think your light would have caused that (but it wouldn't hurt to move them low in your tank and slowly move them up higher just in case).

 

[gdtpgh]

My Lamotte test kit produces results in ppm. I know there are calculators online to convert to the other measures but I simply rely on the ppm and try to get in between 125 and 200 ppm CaCO3 equiv. I would think that if I had issues with calcium or alk my other SPS would have issues as well. That's why I'm questioning lighting and position. I don't have a lot of experience with SPS. My previous tank was mostly soft corals and LPS.

 

[pscheel]

Here is a conversion chart. I prefer my alk to be 9-10.
http://ozreef.org/library/tables/alkali ... rsion.html

When I usually get a new coral, I usually will look what lighting its been under and how long it has been kept in the tank. If it was under high lighting for a long period, I place it high in my tank. If it has only been at the LFS for a short time (which is usually the case) I start the coral close to the sand bed and move it up a few inches a week until it goes to the spot where I want it to go.

 

[Anonymous]

My Lamotte test kit produces results in ppm.

What do you know, I learned something new.
I've never used those kits, but have heard they are top notch.

If those tests are accurate, I'd say your alk was a little low for that Ca level, but probably not by enough to cause any problems (and some people would probably disagree that it is low at all).

In that case, I think your initial suspicion might be correct. It might be worth while to put the affected corals on the bottom of your tank and slowly raise them up after some time. But I think live aquaria has pretty bright lights, so I'm still a little skeptical about the lighting angle. But it wouldn't hurt.

 

[gdtpgh]

I was reasearching this site regarding my issues and found some old messages about mixing Leather corals and SPS. The Montipora is the closest coral to my leather although it's about 8 inches away.

I have yet to move the coral. I also read that I may just be seeing signs of growth?

 

[eric.m.s]

how often do you clean your glass and what skimmer are you running? pictures of the coral would help.

my bet is, you're either nitrogen limited and too low nutrient or it's getting blasted by too much light and causing some bleaching. what's your bioload like?

 

[gdtpgh]

How often do I clean my glass? What could that possibly matter? If it's pertinent, I clean is every weekend as a matter of habit.

This is a new tank with a very light load, 2 green chromis, three fire fish and a hawkfish. I also have some turbo, nasarius, nerith snails and three fighting conchs. I also have a detritivore kit added to the refugium and main tank. All LPS (Candy cane & Frogspawn) are doing wonderful. Other SPS have polyps fully out and growing. Mushrooms, ricordea and Palythoa all growing and in good health. There is also a sand bed of several inches.

What does "nitrogen limited" mean? I'm not at all familiar with that term. Nitrates and nitrates all zero. I use RO/DI water with brand new filters. I use Carbon for two weeks/month. Water is clear. My skimmer works well and I empty it every few days. I also feed mysis to the fish and oyster eggs to the corals every so often.

As I mentioned, I have zero experience with SPS and don't know the nuances of their growth. This new tank has much better/stronger lighting than my old tank and I just don't know if what i'm seeing is ok or something to be concerned about.

To really dicern a difference you'd need a before and after pic. Unfortunately I don't have a before pic. The Montipora has grown since I got it. It's just the color that's faded and the polyps aren't out as much as before.